Matchup: Despite Portland’s expansion status, the Timbers have been a thorny issue for the Galaxy in the Northwest. The Galaxy are 1-3 in their four trips to Portland. ... The Galaxy (2-2-2 in MLS play) will be without defender Omar Gonzalez, who has an injured left knee. Gonzalez suffered the injury in last week’s game at Colorado and was replaced by Kofi Opare, who could get the start in this game. ... On Monday, Landon Donovan is expected to get the call to join the U.S. national team camp. Will he arrive at Stanford as the league’s all-time leading scorer? Donovan has 134 career goals, tied with Jeff Cunningham atop the list. “Every player wants to score and it feels good to score, but I really feel like I’m doing a lot of things that are helping the team and helping us play well,” Donovan said. “Certainly a goal helps, but if I don’t score I still feel good where I’m at going in.” ... Gonzalez is also expected to be called to U.S. duty.